Grinders?

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Ready to add to the quiver and not sure about what size angle grinder is better all around. Figured the more experienced bunch here could lend some thoughts. Currently looking at the Milwaukee variable speed models.Is there really much of a difference in versatility and application between a 4.5" or 5"? I know I'll probably end up with a couple and it seems like the 4.5" is a popular size. Also seems like each size has about the same amount of blades/wheels available.Thoughts?Mike
Reply:5" makes a nice grinder, but all my small grinders are 4.5" for the sheer availability of all kinds of wheels from all kinds of suppliers, and I can keep them all in one box to grab and know they will all fit all of the small grinders, of which I currently have only five.
Reply:The removal is most affected by the feet per minute at the leading edge of the wheel and the torque to keep the rpm up there. Knowing that you'd have to actually be interested enough to do a comparison of the max rpm on each and every grinder you buy to determine if "this" 5 inch was as good as or better than "that" 4.5 inch. What this blather is supposed to mean is that an 8.5 amp 5 inch at 11,000 rpm may not be much better than an 8 amp 4 inch at 13,000 rpm. If the next step up in wheel diameter is also accompanied by a nice step up in amps, then there should be a noticeable difference in removal performance. Like mac says, having mutliple grinders in itself is a huge benefit plus having any wheel (flap, cutting, grinding) you grab fitting whichever grinder you grab is a real plus. If you find a nice 5 inch with some amps that feels good get it, but don't worry over it a lot.
Reply:Personally I love my 5" Metabo's.Go forever, but not cheap.I always buy 5" because a 4 1/2" has the same bore and you have the option of using either size disc, something a 4 1/2" guard wont let you do.
Reply:Like sandy and mac say...buy several.  I have 3 small 4.5 inch ones (dewalt, black and decker, and a no-name) and a 9 inch one (harbor freight).  On my smaller ones, I keep different stuff on them...one is a grinder, the other is a cutting wheel, the third is a wire cup.  I am always tempted to have more grinders.  I bought the 9 inch HF a couple of months back and have been very satisfied.  It's hard to beat paying less than $40 for a big grinder that works, much less one that works pretty well.  I can't speak to the quality difference between the ones I have or between what I have and what I don't.  I have never had any problems out of any of them yet...so...reliability isn't much of an issue...yet.  My black and decker is too loud...the motor is about as loud as the grinding.  As for Matabo's, I have heard lots of priase for them, but I have never used one myself...Smithboy...if it ain't broke, you ain't tryin'.
Reply:There is no "one" grinder to fit all needs.  I like the 4.5 inchers just because the wheels are so readily available and there are a lot of options.  I also have a 7 inch which I use for more aggressive metal removal. I'm not sure there is much value in any in between sizes other than personal preferences.  I would go with multiples a small and one as large as you can afford.
Reply:I tend to prefer 4.5" for the availability of different consumables. And hardness hard disk you want, alll grit types and grades in a tiger wheel, thick and thin cutoff, brushes, you name it. Less selection in other sizes.I have a friend that swears by his 4", since the body and gaurd are smaller, and the unit is lightr, so he can get into significantly tighter spaces.Then again, for the heavy jobs, a 7" does do things fast......Ya know? It kinda depends......
Reply:Thanks all - good feedback. I'm going to pull the trigger on the Milwaukee 4 1/2". Called Milwaukee to confirm - the 4.5/5" are the same tool, just come equipped with one or the other. If i want to move up to a 5", I can order the guard/wheels as such.While I'm at it, I might just add their 14" dry cut saw (been given a pretty good LWS price) - been looking at those as well You only live once, right?Mike
Reply:Get one of the 8.5 amp Milwaukees.  The trigger on the 5.5 amp model isn't very ergonomic.  The 12 amp isn't worth the extra money because you'll never bog down the 8.5 amp anyways.
Reply:I went with the 6154-20, wasn't because of the amps - but I wanted to try the variable speed. We'll see if it's worth it...
Reply:Well .... I thought 4.5" Grinders were good until yesterday.We 'found' 10 frame/fixtures that will yield us about 30 feet +/- of 1" X 2" , rectangle tubing. Today we cut the first one up using thing cutoff wheels and where we could a porta-band saw.Well the thin cutoff wheels wear down quickly and we used several on one of these. I switched to a slightly thicker cutoff wheel.I guess if you are gonna do a lot of cutting with the thinner cutoff wheels a 7" might be a better choice, so I will be adding a 7" to the other 3 4.5" grinders real soon.
Reply:Two nonames; HF, 4.5, one is a grinder, the other is a cut-off wheel. No complaints.....yet.Still A Nub,Bruce The Welding ChefLincoln Weld-Pack 3200 NORWELD StickStanford Hill Farm
Reply:Originally Posted by harcosparkyWell .... I thought 4.5" Grinders were good until yesterday.We 'found' 10 frame/fixtures that will yield us about 30 feet +/- of 1" X 2" , rectangle tubing. Today we cut the first one up using thing cutoff wheels and where we could a porta-band saw.Well the thin cutoff wheels wear down quickly and we used several on one of these. I switched to a slightly thicker cutoff wheel.I guess if you are gonna do a lot of cutting with the thinner cutoff wheels a 7" might be a better choice, so I will be adding a 7" to the other 3 4.5" grinders real soon.
Reply:Typically I use only Norton Wheels .... just pulled a 10" Norton off my Delta Miter saw to replace with a new one and there wasn't as much wear as I expected.In any case we have switched modes a bit and a fiber cutoff wheel is now a tool of last resort.Gonna rely more on my plasma cutter for tearing stuff up, and trimming/ cleaning it with the porta-band or cold cut blade that we just put into the Delta.  $40 for a Freud blade ..... 12 cuts in and I love that bladeI'll use grinders to clean up outside corner welds and stuff like that. ( ya know spin a wire brush/flap wheel for steel clean up )I'm new to this ( welding ) and learning all the processes is almost as tough as learning to weld.My problem comes from wanting perfection in things like mitered corner joints, in woodworking it had to be PERFECT if not the glue line in the joint would detract from the overall project.We live , we learn , we move on to learn some more!  Oh an by the way, we were cutting up some steel frames we found made of  1" X 2" rectangle tubing 1/8" thick. I didn't count the cuts but there had to be 30 or more per each unit and many were "inside" making them hard to get to.Last edited by harcosparky; 11-07-2006 at 06:52 PM.
Reply:Dad bought a 4.5" one from harbor freight, it's been a good grinder so far. It's the orange and black one if that makes a difference. I like it but it's nothing compared to the DW402's we used at the shop in high school. I give it a thumbs up, because I ran it with 115 volts DC off of the outlet on the welder and it ran just like it did on AC current.Last edited by RobertDoubrava; 11-07-2006 at 07:59 PM.RD 1984 Chevrolet C30 welding truck1966 Lincoln SA200 Continental F162 1942 Lincoln SA200 Hercules IXB-51991 Lincoln LN25
Reply:Some grinders are dual rated for AC and DC voltage.  I know the 5.5 amp and 7 amp Milwaukees are.
Reply:i have 4 of the 4.5" 2 are the lighter duty B&D's and 2 are portacables with the padle triger and a 7.6 amp motor, you defenetly want the extra amp's, the lil 5amp B&D's work ok with the wire wheel but the cup's dont do so well on it, the portacables are a much nicer grinder. there is a big diference between the cheepos and the good ones, i can tell that from mine and i only have the ok ones, some day i'll get a few of the realy good ones. the cheepos off e-bay are a waist of time & $$$ the millwa. should serve you well.when i'm doing demmo work to get spare matereals i use my sawsall a lot and also a disk on my 8.5" worm drive skill saw, the disks dont last near as long as the sawsall's though. summer is here, plant a tree for mother earth. if you dont have time or space, sponcer some one else to plant one for you.feel free to shoot me a PM or e-mail me at [email][email protected] i got lots of time.
Reply:I just bought an $18 one at harbor freight, finally couldn't resist. Hey the thing works, I'm gonna buy a couple more and never have to switch between flap wheel, grinder, and wire wheel. Ugh I feel so dirty starting to actually enjoy horrible freight products. I have a couple of pneumatic staplers that I like too...guess I've become part of the problem, buying the cheap junk instead of American. Then again my milwaulkee heat gun that I've used maybe 5 times just stopped working....
Reply:Ridgid (aka Metabo 4 1/2") - Heavy as a Tank... but good for bigger jobs.  Lightweight plastic bodied Makita 4" for 1-hand cutting and severing instead of grinding.I need 1 more to put a flap disc on.TOOLandFAB.com See our Articles and Member Writeups and Tool Review Sections
Reply:I've never seen a variable speed grinder.  Can anybody explain to me the utility of variable speed in a grinder?  Seems like only an advertising advantage.  When I'm grinding, I usually want all the speed I can get.  If I want finesse, I use a finer grit wheel at full speed.For heavy stock removal, my 7" B&D can't be beat.  It's the old, heavy-duty industrial type with all-aluminum body.  It has served well for about 30 years and I bought it used.  Still going strong, although I had to replace the switch a decade ago.My most recent grinder purchase was a DeWalt, selected primarily on the basis of amp rating.  I like it.  My Makita 4.5" has lasted severa; decades and given a lot of service, but is wearing out and getting very noisy and will probably die soon.   A green no-name that I got as a gift is a joke.  It lugs down at the slightest touch to the work.awright
Reply:yep spend some $$ here for a good one, the only advantage to the B&D's i have is when they burn up wallmart gives me a new one. the porta's are running strong. summer is here, plant a tree for mother earth. if you dont have time or space, sponcer some one else to plant one for you.feel free to shoot me a PM or e-mail me at [email][email protected] i got lots of time.
Reply:I'm with Sandy I have a couple of 5" Metabo's tough as nails a bit pricey but well worth it also have a few 4" bosch grinders they don't see much use anymore Creative metal Creative metal Facebook
Reply:Originally Posted by 76GMC1500Some grinders are dual rated for AC and DC voltage.  I know the 5.5 amp and 7 amp Milwaukees are.
Reply:I've got one 5", 12 amp Milwaukee that's variable. Not variable through the trigger but variable by means of a numbered thumb wheel at the butt of the grinder. Tried it a few times then put it back on warp drive and leave it there.It could be good for light buffing or or thin body work or something like that maybe. Dunno. If I ever run into a sutuation where I could use it, I'll probably forget that I've got it.
Reply:Most any tool with a "universal motor," that is, a motor with brushes and a wound field (as opposed to a permanent magnet field - rare in a line operated tool) works fine on DC as well as AC whether they say so or not.  They may not mention it because 120 VDC is pretty rare and not something that the package designers and marketers are concerned about catering to.A proplem could come up with a tool having a variable speed control, since virtually all of those will rely on the zero crossing of the AC waveform to commutate the SCR or Triac, that is, turn it off in preparation for the next time delay as controlled by the amount of trigger depression.  Such a speed control will not be damaged, but will probably exert no control after the initial turn on with DC power.If it has brushes and does not have variable speed, I would use it on DC with no concern.awright